Conventional quartz clock comprising a coil and a permanent magnet is operated by the magnetic repulsive force to cause the continuous oscillation of clock body or pendulum. In this way, a fixed clock body B with a pendulum pivotedly formed on the clock body as FIG. 1 shown, or a swinging casing A including clock body B and pendulum being pivotedly mounted on a pole C as FIG. 2 shown were disclosed. In FIGS. 2 and 3, the rhombic pole C is formed with two fulcra d1, d2 on its top portion to support the swinging casing A and clock body B at an inversed V-slot f formed inside a sleeve e of casing A. The gravity center of this rocking clock can be adjusted to exactly locate between two fulcra d1 and d2. However, such conventional rocking clocks as shown in FIGS. 1 and 2 still have the following defects:
1. To correspond the induction coil a on the swinging casing A, a magnet b is fixedly positioned so that it is suitable only for specific size of clock diameter.
2. Two fulcra d1, d2 are fixedly positioned on rhombic pole C and the inversed V-slot f is also formed in a fixed position inside the sleeve e so that their fabrication should require high precision technique to increase the production cost.
3. To use this type of clock, it is necessary to adjust the inversed V-slot f of sleeve 3 to fall between two fulcra d1, d2. This can be done only by a skilled person.
4. When encountering environmental vibration, the inversed V-slot will easily slide between two fulcra and the distance between permanent magnet and induction coil will be influenced to easily stop the swinging motion of clock.
5. The pendulum g hung on the clock is very light and is easily oscillated in an irregular way by air blowing or other reasons.
6. The contact area between the rhombic fulcra d1, d2 and extensions d3, d4 is so large, which may increase the abrasion therebetween and may even stop the swinging of pendulum.
The present inventor has found the defects of conventional clocks and invented the present electromagnetically-induced rocking clock.